Infiniti Q50 vs Mercedes-AMG E43

What's the difference?

The Q50 Red Sport is a premium sedan that's great value, with a cracker of an engine. While Infiniti has improved the ride and steering, it still feels to me that the engine is too powerful for the wheels and chassis to handle. But if you're looking for something of an untamed beast, this car could be for you. Just don't say we didn't warn you.

If you want a fast Benz but your other half prefers genuine comfort and doesn't like the sound of NASCAR, this is your solution. It's an opulent luxury saloon by default, but with proper performance and personality just the flick of a switch away.

We know the E 63 S will be sharper and 1.2s quicker to 100km/h, but it will also cost another E 200 more, and feel like a performance car ALL the time. The E 43 doesn't, which is just brilliant.

The Q50 Red Sport looks cranky from front on, which I like in a car. Yes, the grille is simplistic and gaping, the nose is a bit bulbous, and sure, side on the car looks like a Lexus IS 350, but those rear haunches and the aggro body kit with its front splitter and boot lid spoiler make for an impressive looking four-door sedan.

The update brought restyled front and rear bumpers, those red brake calipers and the dark chrome 20-inch rims and new LED tail-lights.

Inside, the cabin is an asymmetrical paradise (or hell, if you're a bit OCD like me) full of sweeping lines, angles, as well as different textures and materials.

The red stitched quilted leather seats are an addition that came with the update, so is the new steering wheel and the ambient lighting.

The 'Sunstone Red' colour of our test car is also a new hue which looks a bit like Mazda's Soul Red. If red is not you, there are other colours – hope you like blue or white or black or grey because there's 'Iridium Blue', 'Midnight Black', 'Liquid Platinum', 'Graphite Shadow', 'Black Obsidian', 'Majestic White' and 'Pure White'.

The Q50 has similar dimensions to the IS 350: both are 1430mm tall, the Infiniti is 10mm wider at 1820mm,  120mm longer at 4800mm, and has a wheelbase that's 50mm longer at 2850mm.

Unlike the bulging wheelarches and gaping gob of the new E 63, the E 43 uses discrete flourishes to distinguish it from the regular AMG-pack E-Class.

Most obvious are the more aggressive 20 x 8 and 20 x 9 'RTO' wheels, but if you look closely it also scores subtle black winglets on the outer edges of the front bumper openings, a single bar grille insert, boot lip spoiler and black split exhaust tips. 

Hiding within those wheels are upgraded 360mm brakes at all corners, with four piston calipers up front and single at the rear.

On the inside, the E 43 steps up to perforated leather and 'Dynamica' pseudo suede seat trim but the fronts appear to be the same comfortable shape as the regular AMG pack seats. Aside from a smattering of AMG badges, that's about it. Like the outside, it looks a little bit sporty, but luxury is the focus.

The Q50 Red Sport is a five-seat four-door sedan and is vastly more practical than its two-door Q60 Red Sport sister, in that I can actually sit in the back seat. The Q60's coupe styling looks amazing, but the sloping roofline means headroom is so severely limited that it reduces the rear seats to a place to throw your jacket.

True, I'm tall at 191cm, but in the Q50 Red Sport I can sit behind my driving position with legroom to spare and more than enough headroom.

Boot space is good at 500 litres, which is 20 litres more than the luggage capacity of the IS 350.

Storage throughout the cabin is good with two cup holders in the rear centre fold-down armrest, two more up front and bottle holders in all doors. A large centre console storage bin and another big storage area in front of the shifter are great for keeping junk under control and your valuables covered.

Like all E-Class sedans, the E 43 has amble room for four large adults to travel comfortably. Everyday practicality is well considered with dual cup holders front and rear with bottleholders in each door, map pockets and ISOFIX child seat mounts in the outer rear positions. Boot capacity is a useful 540 litres.
Like all AMG performance models, the E 43 forgoes run-flats or a spare tyre in favour of an inflation kit.

At $159,900 the E 43 sits exactly $20,000 above the E 400. As you'd expect it comes fully loaded with comfort and convenience features, including a choice of black, brown or beige nappa leather, 'Air-Balance' cabin scent and air filtration system, tinted windows, panoramic sunroof, head-up display and a 13-speaker Burmester surround sound audio system.

Like all new E-Classes, the E 43 also comes with the brilliant Drive Pilot suite of active cruise control and lane guidance tech that permit semi-autonomous driving, including the ability to change lanes. More sculpted AMG front seats and a Dynamica pseudo suede-trimmed steering wheel are available as a $3076 option, but it's worth noting that the seat upgrade eliminates the PRE-SAFE impulse side function that moves passengers toward the centre of the car when a side collision is anticipated.

Inside the Q50 Red Sport's nose is a 3.0-litre twin-turbo V6 petrol engine and it is a beautiful thing. To me this car is piece of technologically sophisticated jewellery that cradles a precious gem that pumps out 298kW/475Nm.

But I have my concerns... you can read about those in the driving section.

Shifting gears is a seven-speed automatic which delivers drive to the rear wheels.

Rather than simply plonking the 3.0-litre twin-turbo V6 from the other '43s in the E-Class body and fettling the tune to edge it ahead performance-wise over the smaller models, the E 43 uses larger turbos to boost power by 25kW but retains the same 520Nm, which is also 50kW and 40Nm greater than the E 400.

Like all current E-Class variants, the engine is backed by Mercedes' very clever nine-speed torque converter auto and follows the E 400 and other '43s by sending power to all corners via the 4Matic all-wheel drivetrain.

Infiniti says the V6 petrol engine in the Q50 Red Sport should use 9.3L/100km if you're using it on a mix of highways, urban streets and country roads. We only had the Q60 Red Sport for 48 hours and after a couple of days of Sydney city commutes and a trip to the Royal National Park our trip computer was reporting 11.1L/100km.

Despite making more power and torque, the E 43 carries the same 8.4L/100km official combined figure as the E 400, but requires more expensive 98RON to achieve it. The E 43 also scores a 14-litre larger 80-litre fuel tank, which should stretch the range between fills by around 167km based on the official figure.

Perhaps the biggest complaint we had about the previous Q50 Red Sport, which launched in 2016, was that it felt as though the chassis wasn't up to the amount of grunt running through it, and those rear wheels struggled to transfer the oomph to the road without losing traction.

We experienced the same issue again in this new car. I was breaking traction, not just in 'Sport+' and 'Sport' modes, but in 'Standard' and 'Eco', too. That was happening without pushing it hard and with all electronic traction and stability aids on.

If I was 18 I'd declare to the world I'd found my dream car - something that always wants to 'light 'em up' given half a chance. But like that one mate who always gets into trouble on a night out it's only funny when you're young.

A truly great performance car is planted, balanced and able to deliver the grunt to the road effectively. The Nissan R35 GT-R is the perfect example – a brilliant piece of machinery, a weapon of a performance car and with a chassis matched perfectly to its engine.

And that could be the issue with Q50 Red Sport - that engine feels overpowered for the chassis, and wheel and tyre package.

We also felt the previous Q50 Red Sport's ride, with its constantly adapting 'Dynamic Digital Suspension', was overly busy. Infiniti says it has developed the suspension system further and it does feel as though the ride is more comfortable and composed.

Steering was another area that we weren't overly impressed with when we drove the previous car. Infiniti's 'Direct Adaptive Steering' (DAS) system is super sophisticated and was the first in the world not to have any mechanical connection between the steering wheel and the wheels – it's all electronic.

The new Q50 Red Sport uses the upgraded 'DAS 2' and while it feels better than before, it's only in Sport+ mode that it seems most natural and accurate.

Working our way out of Melbourne via its network of motorways, there's little aside from perforated leather and Dynamica faux suede seats to tell us we're aboard something a bit more special than most E-Classes. 

Left in Comfort mode via the console-mounted drive select toggle, the engine delivers a creamy urge with max torque available from 2500rpm, the transmission is silken and the ambience is very E-Class.

On the country roads beyond Melbourne's urban limits, you can tell you're riding on 20-inch wheels with limited sidewalls, but it's all entirely liveable and still very Mercedes. 

Flick it over to Sport mode and it's much the same, but confronted with the bitumen rollercoaster that is Chum Creek Rd (look it up, it's worth it), we felt it was time for Sport +. Race mode is reserved for the full-blown AMGs, but Sport + instantly transforms the E 43. 

The steering gets heavier, the exhaust gets louder and the transmission drops at least one ratio, but the dampers also become much firmer which makes it feel at least a couple of hundred kilos lighter than the aluminium-abundant W213 E-Class already is.

The stability control also loosens its leash and surprisingly permits some play from the rear end when you're really pushing under throttle. It is all-wheel drive, but the torque bias favours the rear wheels by a factor of 69:31.

The auto manages to shift quickly and the abundance of ratios means it happens very often. You'd have to be pretty bored to bother with the paddle shifters, as everything responds beautifully to your right foot – including the brakes. 

It's very easy to drive very fast and you soon forget you're driving a near-5m long sedan.

The V6's growl will never match a V8 symphony, but it helps to stamp the E 43's individual character. If it made no noise it would be disappointing, but it does well to push a classic V6 bark past its turbos.

Like all versions of the W213 E-Class, the E 43 carries the maximum five star ANCAP and EuroNCAP safety ratings. A brilliantly integrated suite of active and passive safety features go well beyond its nine-airbag count, 360-degree parking cameras, rear cross-traffic alerts, and a pedestrian-protecting active bonnet.

The Q50 Red Sport is covered by Infiniti's four year/unlimited kilometre warranty with servicing recommended every 12 months or 15,000km.

Infiniti has a scheduled servicing program which will cost $1283 (in total) for three years.

As with all Mercedes passenger cars, the E 43 is covered by a three-year, unlimited kilometre warranty. Service intervals are either 12 months or 25,000km and the first three services are capped at $668, $1356 and $1356 respectively.